Ladder construction



June 17, 1941. L. s. WILBUR 2,245,888

LADDER CONSTRUCTION Filed Oct. 25, 1939 LA WRENCE S. W/LBUR Patented June 17, 1941 LADDER CONSTRUCTION Lawrence S. Wilbur, Chicago, Ill., assignor to Carter Blatchford, Incorporated, Chicago, 111., a corporation of Illinois Application October 23, 1939, Serial No. 300,779

Claims.

The present invention relates in general to ladders and is particularly concerned with improvements in ladder constructions of the type utilized in conection with railway freight cars.

It is a primary object ofthe present invention to provide an improved ladder construction of the type wherein the rungs are interlockingly connected to the stiles without the employment of any fastening elements therebetween, such connection being so arranged as to positively and rigidly retain the rungs against movement, even though the ladder is subjected to the most severe service usage.

A further object of the herein described invention is to provide in ladders of such type an improved interlocking arrangement betwen the stiles and the rungs, wherein the ladder parts are clampingly engaged.

A still further object of the invention is to provide an improved stile which is so arranged that, when it is secured to a supporting surface, it will be actuated into clamping engagement with the associated rungs.

Another object is to provide a ladder having interlocking stiles and rungs, wherein all the rungs may be similarly constructed, without the necessity of having so-called righ and left rungs.

.Stiil another object is to provide a novel ladder construction wherein th rungs are associated with the stiles of the ladder in such a way as to eliminate the possibility of personal injury to those using the ladder, as by the hands being pinched between adjacent portions of the rungs and stiles.

. Yet another object is to provide a ladder of improved rigid construction, wherein the parts are such as to enable their being fabricated at low manufacturing cost and with a minimum of manufacturing operations.

Other objects and features of the invention will more fully appear from the following detailed description taken in connection with the accompanying drawing which illustrates a single embodiment thereof, and in which:

Figure 1 is a side elevation of an end portion of a railway car showing the application of my improved ladder to both the side and end walls of thecar.

Figure 2 is an enlarged section transversely of the ladder, and showing the cooperative relationship between the stiles and rungs as well as the manner in which the ladder is secured to the car, taken substantially on line II-II of Figure 1.

Figure 3 is an enlarged fragmentary detailed view, partly in section, showing the manner in which a stile grippingly clamps an end portion of an associated rung for retaining it against movement.

Figure 4 is an enlarged fragmentary view looking at the rear of the ladder and showing the cooperative relationship between the ends of a rung and the associated stiles, looking substantially along the line IV-IV in the direction indicated in Figure 1.

As shown on the drawing:

For purposes of illustrating the ladder construction of the present invention, the ladder is disclosed in the drawing as being applied to the side and end wall portions of a railway car as generally indicated at A.

Each ladder construction comprises stiles 16 preferably of angle iron, each having angularly disposed flanges H and 2. The flanges II are disposed outwardly, and the flanges l2 are disposed inwardly to provide foot guards.

A series of vertically aligned hole 13 are formed at intervals in the flanges 12 of the stiles to receive and form bearings for a series of ladder rungs l4.

As shown in Figures 2 and 4 in detail, each rung I l comprises a tread portion I5 which terminates at its ends in rearwardly offset portions :5 adapted to extend through and rest in the holes l3 formed in the stiles. The outer end portions of these offsets are deflected to provide angularly disposed end portion-s l1 and 18 at the rung ends, these portions extending in opposite directions. The portions [1 and I8 are also slightly inclined toward the front of the ladder so as to bring their end into the V formed by the associated stile flanges H and i2, and provide abutment points lying substantially in the same plane parallel to the plane of the ladder.

The stiles in the assembled ladder are disposed with their apices forward and their flanges diverging rearwardly, both flanges of each stile being angularly disposed to the plane of the ladder; and the imlermost flanges of the stiles being angularly inclined relative to each other. With this arrangement, the end portions l1 and N3 of the rungs are symmetrically disposed in the V formed by the flanges of each stile. This forms an interlocking connection with the stile flanges respectively opposing lateral movement of the rung ends, when the stiles are longitudinally shifted in opposite directions in the plane of the ladder. Thus the interlocking connection between the stiles and the rungs eiiects a rigid construction.

The rigidity of the assembled ladder as well as the prevention of the rungs becoming loose is augmented by eifecting a gripping or clamping action between the edges of flange I2, which define the hole l3, and the associated offset portion l6 therein. This action is illustrated in Figure 3. The stiles are secured to angle brackets I9 as by bolts 20, these brackets also being arranged to be secured directly to the wall of 1c car as by bolts 2|, or to a bridging strip which may in turnbe secured to the car wall.

The offset portions iii are arranged at such an angle with reference to the tread portion 15 of the rung that, when this portion is inserted in the hole l3, the stile will be slightly displaced from its normally secured position as shown by the dotted lines in Figures 2 and 3. Tightening of the bolts 20 which secure the stile to the supporting brackets tends to draw the stile into the position shown in full lines and swing the stileso that "the flange I2 is now disposed at a slight angle to the associated portion it of the rung and the hole edges of the hole i3 will grip the portion [6. With this clamping or gripping action, there is no chance for the rung to work loose over long periods of service and will always be maintained rigid and tight in the stiles.

By disposing the stiles as described above, the portions I6 need only be deflected a slight angle and it is also possible to utilize a relatively wide space between the adjacent inwardly disposed marginal edges of the flanges 12 and the adjacent portions of the rungs so that there is no danger of a users fingers being pinched and injured.

The ends of the stiles may be left square as shown at the bottom ends of the stiles in Figure 1, or if desired th ends may be curved as shown for the top ends of the stiles. One convenient way of curving the stile ends is to impart a twist -to the angle iron to bring one of its flanges outermost, for example, flange l2. By cutting away the end margin of the other flange, in this case flange I|,'flange i2 may then be readily curved to guard the end of the stile and prevent a users clothing from catching thereon.

As previously pointed out, the deflected end portions l1 and 1'8 associated with the respective stiles are deflected in the same direction at each stile. That is, the portions I! may all be deflected downwardly, and the portions l8 up'wa'rdly. This is a very desirable features in that the rungs are all similarly constructed and the necessity for the use of right and left rungs is entirely eliminated. However, if desired, right and left rungs may be utilized if desired. In such an arrangement, one or more of the rungs would have their end portions l8 deflected downwardly and their end portions H deflected upwardly, just the reverse of the construction disclosed in the drawing. It will be appreciated that where the two types of rungs are utilized, additional equipment is necessary in the manufacture of the rungs, and the cost is thereby increased. 1

From the foregoing description, it will be apparent '"that'th'e present invention provides an improved ladder construction wherein the rungs and stiles are interlocked without the employment of fastening elements, and that the rungs are rigidly retained against movement by being clampingly gripped by the stiles of the ladder;

which is so arranged that when the ladder is,

secured in supported position, the stiles will be actuated into clamping engagement with the rungs; which provides a construction in which all the rungs may be similarly constructed without having to use so-called right and left rungs; which reduces to a minimum the possibility of pinching or otherwise injuring the hands of a user; and which utilizes parts of such construction and design as to enable their being fabricated at low manufacturing cost and with a minimum of manufacturing operation.

Now, it is of course to be understood that although I have described in detail the preferred embodiment of my invention, the invention is not to be thus limited, but only insofar as defined by the scope and spirit of the appended claims.

I claim "as my invention:

1. A ladder comprising stiles and a plurality of detachable rungs, each stile having flanges diverging rearwardly and inclined relative to the plane of the ladder and formed with a hole in one of its'flanges, said rungs having hole engaging portions and oppositely bent end portions each inclined in a direction from said hole engaging portion toward the front of the ladder to abut the other of the flanges at points respectively above and below said holes.

2. A ladder comprising stiles and a plurality of detachable rungs, each stile having diverging flanges and positioned with its flanges extending at an angle to the plane of the ladder, one of the flanges of each stile being formed with a hole therein, said rungs having holeengaging portions and oppositely bent end portions abutting the stile flanges in the V formed thereby.

3. A ladder comprising stilesa'nd a plurality of detachable rungs, each stil having diverging flanges and formed with a hole in one of its flanges, said rungs having hole engaging portions and deflected end portions abutting the stile flanges in the V formed thereby, the stiles being so positioned with relation to the associated deflected end portions as to provide spaced abutment points thereon lying substantially in a plane parallel to the plane of the ladder.

4. 'A ladder comprising stiles and a plurality of detachable rungs, each stile having diverging flanges and formed with a hole in one of its flanges, said-rungs having hole engaging portions and deflected end portions abutting the stile flanges in the V formed thereby, said stiles being disposed with their apices forward to lock the stiles against relative lateral movements in 0pposite directions in the plane of the ladder.

5. A ladder comprising a pair of spaced stiles and a plurality of detachable rungs therefor, said stiles having facing flanges disposed in relatively inclined angular relation and formed with holes therein, each rung having offset end portions engaging said holes and deflected end portions abutting said flanges.

6, A ladder construction comprising a stile 'formed with a hole "therein, a rung having an of its'divergent flanges and rungs having portions engaging :the stiles in said holes, each rung having oppositelybent end portions, the end portions of the rungsat the respective sides of the ladder being deflected in the same direction, and said angle bars being disposed with their facing flanges in angular relation, the V of each angle bar receiving the associated end portions of the rungs therein for locking the rungs at each stile against general endwise movements in opposite directions.

8. In a ladder, a pair of spaced parallel stiles and a plurality of detachable rungs, said stiles each comprising divergent flanges positioned at an angle of sugstantially 90 to each other and with their innermost flanges oppositely inclined relative to the plane of the ladder, each of the innermost flanges having holes therein, and said rungs each comprising a tread portion, angularly deflected hole engaging portions extending respectively from the tread portions, and oppositely bent end portions extending from the hole engaging portions for abutting the flanges of each stile in the angle formed by the flanges thereof.

9. In a ladder construction, a pair of spaced parallel stiles each comprising divergent flanges and a plurality of detachable rungs, one flange of each of said stiles having holes therein, and

said rungs each having portions adjacent its ends arranged to respectively extend through said holes in a direction substantially normal to the flanges, and supporting means for the stiles arranged to tilt the flanges thereof relative to the portions of the rungs passing through said holes and cause the edges of the holes to clampingly grip said associated portions and retain the rungs against movement.

10. In a ladder construction, a pair of spaced parallel stiles and a plurality of detachable rungs, said stiles having facing flanges inclined relative to the plane of the ladder and provided with holes therealong, and said rungs each having portions adjacent its ends arranged to respectively extend through said holes in a direction substantially normal to the flanges, and supporting means for the stiles arranged to tilt the flanges thereof relative to the portions of the rungs passing through said holes and cause the edges of the holes to clampingly grip said associated portions and retain the rungs against movement.

LAWRENCE S. WILBUR. 

